Not every conversation deserves its own project. A floating button, available from any index view, opens a quick conversation panel without asking you to create or open a workspace first.
Under the hood these aren't a special hidden concept — they're ordinary threads, quietly kept in a workspace of their own so they show up in your regular workspace list too, if you ever want to browse them the long way.
Closing the panel and navigating elsewhere doesn't lose your place — reopening it returns you to the same conversation, or the same recent-threads list, exactly where you left it.